Alien apocalypse: Can any civilization make it through climate change?

June 5, 2018, University of Rochester
A case study of the inhabitants of Easter Island served in part as the basis for a mathematical model showing the ways a technologically advanced population and its planet might develop or collapse together. Rochester astrophysicist Adam Frank and his collaborators created their model to illustrate how civilization-planet systems co-evolve. Credit: University of Rochester illustration / Michael Osadciw

In the face of climate change, deforestation and biodiversity loss, creating a sustainable version of civilization is one of humanity's most urgent tasks. But when confronting this immense challenge, we rarely ask what may be the most pressing question of all: How do we know if sustainability is even possible? Astronomers have inventoried a sizable share of the universe's stars, galaxies, comets, and black holes. But are planets with sustainable civilizations also something the universe contains? Or does every civilization that may have arisen in the cosmos last only a few centuries before it falls to the climate change it triggers?

Astrophysicist Adam Frank, a professor of physics and astronomy at the University of Rochester, is part of a group of researchers who have taken the first steps to answer these questions. In a new study published in the journal Astrobiology, the group—including Frank, Jonathan Carroll-Nellenback, a senior computational scientist at Rochester, Martina Alberti of the University of Washington, and Axel Kleidon of the Max Planck Institute for Biogeochemistry—addresses these questions from an "astrobiological" perspective.

"Astrobiology is the study of life and its possibilities in a planetary context," says Frank, who is also author of the new book Light of the Stars: Alien Worlds and the Fate of the Earth, which draws on this study. "That includes 'exo-civilizations' or what we usually call aliens."

Frank and his colleagues point out that discussions about rarely take place in this broader context—one that considers the probability that this is not the first time in cosmic history that a planet and its biosphere have evolved into something like what we've created on Earth. "If we're not the universe's first ," Frank says, "that means there are likely to be rules for how the fate of a young civilization like our own progresses."

As a civilization's population grows, it uses more and more of its planet's resources. By consuming the planet's resources, the civilization changes the planet's conditions. In short, civilizations and planets don't evolve separately from one another; they evolve interdependently, and the fate of our own civilization depends on how we use Earth's resources.

In order to illustrate how civilization-planet systems co-evolve, Frank and his collaborators developed a mathematical model to show ways in which a technologically advanced population and its planet might develop together. By thinking of civilizations and planets—even alien ones—as a whole, researchers can better predict what might be required for the human project of civilization to survive.

"The point is to recognize that driving climate change may be something generic," Frank says. "The laws of physics demand that any young population, building an energy-intensive civilization like ours, is going to have feedback on its planet. Seeing climate change in this cosmic context may give us better insight into what's happening to us now and how to deal with it."

Four scenarios for the fate of civilizations and their planets, based on mathematical models developed by Adam Frank and his collaborators. The black line shows the trajectory of the civilization's population and the red line shows the co-evolving trajectory of the planet's state (a proxy for temperature). Credit: University of Rochester illustration / Michael Osadciw

Using their , the researchers found four potential scenarios that might occur in a civilization-planet system:

  1. Die-off: The population and the planet's state (indicated by something like its average temperature) rise very quickly. Eventually, the population peaks and then declines rapidly as the rising planetary temperature makes conditions harder to survive. A steady population level is achieved, but it's only a fraction of the peak population. "Imagine if 7 out of 10 people you knew died quickly," Frank says. "It's not clear a complex technological civilization could survive that kind of change."
  2. Sustainability: The population and the temperature rise but eventually both come to steady values without any catastrophic effects. This scenario occurs in the models when the population recognizes it is having a negative effect on the planet and switches from using high-impact resources, such as oil, to low-impact resources, such as solar energy.
  3. Collapse without change: The population and temperature both rise rapidly until the population reaches a peak and drops precipitously. In these models civilization collapses, though it is not clear if the species itself completely dies outs.
  4. Collapse with resource change: The population and the temperature rise, but the population recognizes it is causing a problem and switches from high-impact resources to low-impact resources. Things appear to level off for a while, but the response turns out to have come too late, and the population collapses anyway.

"The last scenario is the most frightening," Frank says. "Even if you did the right thing, if you waited too long, you could still have your population collapse."

The researchers created their models based in part on case studies of extinct civilizations, such as the inhabitants of Easter Island. People began colonizing the island between 400 and 700 AD and grew to a peak population of 10,000 sometime between 1200 and 1500 AD. By the 18th century, however, the inhabitants had depleted their resources and the population dropped drastically to about 2,000 people.

The Easter Island population die-off relates to a concept called carrying capacity, or the maximum number of species an environment can support. The earth's response to civilization building is what climate change is really all about, Frank says. "If you go through really strong climate change, then your carrying capacity may drop, because, for example, large-scale agriculture might be strongly disrupted. Imagine if climate change caused rain to stop falling in the Midwest. We wouldn't be able to grow food, and our population would diminish."

Right now researchers can't definitively predict the fate of the earth. The next steps will be to use more detailed models of the ways planets might behave when a civilization consumes energy of any form to grow. In the meantime, Frank issues a sober warning.

"If you change the earth's climate enough, you might not be able to change it back," he says. "Even if you backed off and started to use solar or other less impactful resources, it could be too late, because the planet has already been changing. These models show we can't just think about a evolving on its own. We have to think about our and civilizations co-evolving."

Explore further: We think we're the first advanced earthlings—but how do we really know?

More information: A. Frank et al, The Anthropocene Generalized: Evolution of Exo-Civilizations and Their Planetary Feedback, Astrobiology (2018). DOI: 10.1089/ast.2017.1671

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Thorium Boy
2.7 / 5 (19) Jun 05, 2018
Had to drag the man-made global warming propaganda off-world?
Parsec
4.3 / 5 (8) Jun 05, 2018
As I have said before, it is very unlikely under any imaginable scenario that man would actually become extinct. It is likely that our civilization would collapse with a large die-off, but even so, mankind is kind of like cockroaches in their ability to survive in the most extreme environments. Maybe not in great numbers, but certainly at a sustenance level.
poksnee
2 / 5 (16) Jun 05, 2018
I agree with Thorium Boy.

antialias_physorg
3.5 / 5 (8) Jun 05, 2018
mankind is kind of like cockroaches in their ability to survive in the most extreme environments.

I dunno. There are pretty narrow ranges of temperature/oxygen levels/whathaveyou that are required for human survival. Humans (as a species) are nowhere as biologically resilient as some other species. Don't let our ability to locally change environments through technological means fool you. That doesn't work over long periods of time if the outside is downright hostile (look at experiments like Biosphere 2)
Anonym
2.5 / 5 (13) Jun 05, 2018
Amazing the stuff people come up with. Here we have four scenarios which a high school senior could have sussed out, no advanced degree required! The first scenario seems to accept as fact the unproven theory that global warming will result in widespread famine, disease, etc., when the opposite is more likely: higher CO2 has boosted agricultural output by an estimated 30 percent and we know from greenhouse operations that they can thrive under MUCH higher CO2 regimes than 400 ppm. The professional fear-monger in this article speculates without any basis that if the Midwest were to dry up due to climate induced drought, we'd all starve but this is nonsense. No one can predict where the rain might fall, but it will fall. Warm air produces more precipitation than cold air.

Technologically, we are well past Peak Environmental Degradation --- that probably occurred in the '70s in the US; we just can't see this because the increase in population since then is masking the trend.
zenga
2.5 / 5 (17) Jun 05, 2018
what bloody nonsense.
orti
1.7 / 5 (11) Jun 05, 2018
"Climate Change Has Run Its Course"

https://www.wsj.c...28152876
antigoracle
2.2 / 5 (13) Jun 05, 2018
WOW!!
The astonishing bullshit of the AGW Cult and their PATHOLOGICAL "science" has now truly gone astronomical.
MR166
1.9 / 5 (9) Jun 05, 2018
The Green movement is just a useful tool of Marxist ideology. That is why the movement is embraced by the US educational system. The purpose of the movement is to reduce the economic vitality of the west. That along with uncontrolled immigration is calculated to create the revolution needed to destroy the capitalist system.
rrwillsj
3.6 / 5 (9) Jun 05, 2018
A pretty stupid bunch of denier agitprop by the bumblers of altright fairytails. Who are incompetent to understand the difference between Global Warming and Climate Change. Who confuse the theories of marxism and capitalism with the reality, that globally, we all live in some variant of the Corporate State. And confuse parrot-roting a few dimly remembered pseudo-patriotic slogans to avoid the responsibilities of living in this modern society. On the only available Living World.

As for the subject, the authors assume (since there is no contradictory proof available) that all technological societies evolve in the same manner. Commit the same mistakes and as intelligent, reasonable, rational sophonts all will share the same existential angst. Unavoidably causing their self-destruction in a suicidal frenzy of greed and hate.

Guess that'll show'em! Explains why no one has shown up to trade trinkets and geegaws and force missionaries onto us benighted savages?

Merrit
2 / 5 (4) Jun 05, 2018
@rrwillsj totally agree. Their analysis only applies to a small subgroup of total alien possibilities. An alien species would likely have very different issues.

Native Americans, for instance had no real effect on climate change and would have likely continued living the way the did for thousands or millions of years into the future.

Not every society by necessity would make scientific progress and ever have the capability of causing climate change
Shootist
1.7 / 5 (6) Jun 05, 2018
humans have made it though climate change since there were humans. idiots.

no reason to believe "aliens" would find existence any different.
antialias_physorg
4.2 / 5 (10) Jun 05, 2018
humans have made it though climate change since there were humans

Climate change doesn't mean what you think it means...idiot.
Mark Thomas
4.2 / 5 (5) Jun 05, 2018
no reason to believe "aliens" would find existence any different.


It stands to reason that alien planets and civilizations are going range from the strangely familiar to the unpredictably bizarre, so all kinds of outcomes are possible. Frankly, I think we are on the unlucky side to have face potentially devastating global warming so briefly into our industrialization period. This may be due to Earth's thin atmosphere and inner habitable zone location.

While a relatively small addition of CO2 here dramatically increases the percentage of infrared blocking CO2, that percentage difference would be a lot lower if the atmosphere were much thicker and already loaded with CO2. Another problem we have is Earth is close to the inner edge of the habitable zone. If Earth were close to the outer edge and all human civilization were clustered around the equator, we might view global warming with gratitude. For example, global warming is exactly what Mars needs.
ShotmanMaslo
3 / 5 (4) Jun 05, 2018
Switching to nuclear is plausible like a century before switching to renewables is. Nuclear is the key to keep CO2 in check while other sustainable energy has time to develop. Species that realize this will avoid catastrophic global warming. Species that develop an irrational fear of nuclear will not.

mankind is kind of like cockroaches in their ability to survive in the most extreme environments.


Cockroaches will die out with the Sun. We need a modern technological civilization or we are doomed in the long term. Subsistence level is as good as being already extinct.
Dug
3 / 5 (4) Jun 05, 2018
Climate change is some what relative to what you have evolved to deal with. Have the researchers completely forgot that our ancestors have adapted to ice ages and then come out (global warming) of them multiple times - all with less technological understanding than we now have. What is different this time is that there are so many more of us relative the critical finite resources our technological survival base depends on and which we are depleting and diluting at an alarming rate.
ddaye
5 / 5 (2) Jun 05, 2018
We've only got evidence from the one civilization that spent the half century, during which climate change knowledge developed, transferring power and asset ownership to the institutions driving the change and which oppose most governmental roles in society and economy. It's possible that a civilization that does not oppose the concept of governing itself might discover climate change and decide to tackle the problem.
malapropism
3.7 / 5 (3) Jun 05, 2018
@rrwillsj totally agree. Their analysis only applies to a small subgroup of total alien possibilities. An alien species would likely have very different issues.

Native Americans, for instance had no real effect on climate change and would have likely continued living the way the did for thousands or millions of years into the future.

Not every society by necessity would make scientific progress and ever have the capability of causing climate change

The original paper is interesting however, if you read it (you may have, I don't know...) because it takes an abstracted approach to the problem and models environmental carrying capacity against per capita generic resource utilisation, albeit in a fairly simplistic way thus far, as the authors themselves acknowledge in the discussion. In this way, the models are applicable to a broad range of non-technological through to high-tech societies (at least in principle and if further developed). This seems good, useful work to me.
rrwillsj
1 / 5 (3) Jun 05, 2018
Two other points everybody misses. First, out of four planets in our Sun's goldilock zone? Only the one you are drunkenly staggering across is habitable for biological organisms. And that is a best case example. Observations of neighboring star systems continue to show diminishing returns for finding Living Worlds.

Second, there are, what? Maybe a dozen or so species that we would consider intelligent by Human standards? The only ones with prehensile digits are well onto their way to extinction. The rest are hanging on by a thread at our sufferance. Cause they're cute and cuddly! Or at least tasty eating.

If our system is normal for a stable G star, billions of years old? At best 25% of the planets may be habitable.

For those with billions of years of habitability? If any species evolves the capability of exterminating it's competition? Well, obviously they deserve their fine dining opportunities.

Bon appetit, mes amis!
Mimath224
not rated yet Jun 05, 2018
I wonder if comparing present day scenario (whatever that might be) with past cultures is a good idea. A few hundred years ago they didn't have aircraft which would be used today to airlift people from one place to another. In addition to I imagine today's shipping technology is also more advanced than what was available to the inhabitants of Easter Island. And no doubt other alternatives would also be available today that wasn't available way back when.
pubwvj
3 / 5 (6) Jun 05, 2018
There are pretty narrow ranges of temperature/oxygen levels/whathaveyou that are required for human survival.

Narrow? You're joking... right? Where I live it gets down to -45°F and up to 86°F. In other places it gets up over 110°F. We survive all levels of humidity. We survive in calm and in high wind. Bright sun and dim forests. Along shore lines and high in the mountains. At plenty of oxygen (coastal) and far lower oxygen levels (high mountains). Quite frankly humans are pretty rugged and where we can't survive we modify ourselves, our coverings, our environment or other creatures around us so that we can survive. Heck, humans thrive under almost all circumstances.
eachus
5 / 5 (2) Jun 05, 2018
The inhabitants of Easter Island could have built a commerce with, say South America, and had access to relatively unlimited resources. Instead, they used up all the trees on the island, and it was too late.

To learn from that lesson, we need to colonize the Moon, Mars and/or the asteroid belt before the resources to do so are no longer available. Actually that converts into building a space elevator on the Earth, the Moon, or Mars as soon as we can.

Space elevators on the Moon or Mars are much easier to build. In fact a reasonable plan for reaching Mars might be to ship the materials for a starter elevator to one of the Martian moons before landing on the planet itself. For the Moon? Ship an elevator from the Earth, then use it to land a colony and mine materials for an Earth elevator.

A small starter elevator for the Moon or Mars is on the order of one large payload from Earth, say a Falcon Heavy. Do it now, and in a hundred years your grandchildren will thank you.
Zzzzzzzz
3.4 / 5 (5) Jun 05, 2018
There are pretty narrow ranges of temperature/oxygen levels/whathaveyou that are required for human survival.

Narrow? You're joking... right? Where I live it gets down to -45°F and up to 86°F. In other places it gets up over 110°F. We survive all levels of humidity. We survive in calm and in high wind. Bright sun and dim forests. Along shore lines and high in the mountains. At plenty of oxygen (coastal) and far lower oxygen levels (high mountains). Quite frankly humans are pretty rugged and where we can't survive we modify ourselves, our coverings, our environment or other creatures around us so that we can survive. Heck, humans thrive under almost all circumstances.


The ranges you are describing are all very narrow. You prove the point with your argument against it.
Zzzzzzzz
1 / 5 (5) Jun 05, 2018
Humans evolved on this planet. Our intelligence and our senses are rudimentary for discerning the planet we live on, and we struggle all our lives to believe we are actually figuring out what our environment is like. Take us off the planet, and we will not survive long at all. Likely we would never successfully reproduce. Therefore, escape from our planetary system will always remain out of reach.

We will not survive, long term. Even if we miraculously keep from drowning in our own excrement, we can never get past the death of our star. The best long term survival hope we can ever have is our progeny, the AI's. AI's can modify themselves to survive off the planet, or perhaps even away from a planetary system. Hopefully they won't be prisoner to the delusions humans cannot escape from, and will be able to better understand the universe, and therefore survive in it. Not to say that their success is assured, but their prospects would be far better than our own.
Surveillance_Egg_Unit
3.3 / 5 (7) Jun 06, 2018
The Green movement is just a useful tool of Marxist ideology. That is why the movement is embraced by the US educational system. The purpose of the movement is to reduce the economic vitality of the west. That along with uncontrolled immigration is calculated to create the revolution needed to destroy the capitalist system.


MAGA
marcush
5 / 5 (5) Jun 06, 2018
Wow, this really drew out the rabid AGW deniers! With Trump steaming ahead, there is no telling when CO2 levels will stabilise. 3C by the end of the century is all people seem to talk about. What about in 200 years? The ultimate strength of positive feedbacks from melting permafrost is anyone's guess and its wise to consider ALL possibilities.
Tyrant
2 / 5 (8) Jun 06, 2018
This anti-science 'global warming religion' needs to stop!
Merrit
4.3 / 5 (6) Jun 06, 2018
@Tryant and all GWD. There is plenty of data out there showing the increase of co2 levels over time as well as the average global temperature. Even if you don't believe that for some reason, the diminishing area of arctic sea ice should clearly show the planet is getting warmer. The only real debate or question is how big of a deal this really is.
ZoeBell
Jun 06, 2018
This comment has been removed by a moderator.
Merrit
5 / 5 (1) Jun 06, 2018
@Zeobell heat would not be an issue for a sufficiently advanced civilization. Heat is just a form of energy and with enough technology could be converted into more useful forms. Cold would be more of a potential problem because you need to use energy to create heat. Conservative of energy.
ZoeBell
Jun 06, 2018
This comment has been removed by a moderator.
Merrit
5 / 5 (1) Jun 06, 2018
@zeobell I don't see how that is an issue. We don't have the technology to do it efficiently ourselves, but theoretically it is possible. You can artificially create the gradient btw.
ZoeBell
Jun 06, 2018
This comment has been removed by a moderator.
Merrit
1 / 5 (1) Jun 06, 2018
@zoo temperature only seems uniform at the everyday level we live on. At smaller scales there are more fluctuations in temperature. I imagine it would be possible to convert heat energy to other forms at the quantum level. Then you just need to do it in parallel. Sorta like a computer cheap.
Merrit
5 / 5 (3) Jun 06, 2018
@zoo I am not surprised the concept of conservation of energy is so hard for you since you believe over unity devices are possible. You do realize that the conservation of energy has never been observed to be broken and that an over unity device would break this right? A sufficiently advanced society would be able to convert energy from one form to another with very little or no enegy lost in the process. Converting heat to other forms of enegy would be part of that.
Mark Thomas
5 / 5 (4) Jun 06, 2018
Therefore, escape from our planetary system will always remain out of reach. . . . We will not survive, long term.


Do you have any idea how pathetic and foolish that sounds? Right up there with "man will never fly" and "everything that can be invented has been invented." There are 9 man-made objects on their way out of the solar system right now. One reached interstellar space over 5 years ago. Is it that hard for you to imagine "escape from our planetary system" is possible? How about in a hundred years or a hundred thousand years?
Merrit
5 / 5 (3) Jun 06, 2018
@zzzzzz and mark also, don't forget we can always bioengineer ourselves. I know this idea isn't very popular, but could be very useful. We already alter ourselves in useless ways such as tattoos. I wouldn't doubt in 50s years people will choose to become cyborgs when artificial limbs and other parts are superior to natural ones. As far as living on other planets we could alter our DNA to help cope with it as well. Obviously, these technologies are futuristic, but very realistic outcomes in the future.
Mimath224
5 / 5 (3) Jun 06, 2018
@Mark Thomas
Therefore, escape from our planetary system will always remain out of reach. . . . We will not survive, long term.


Do you have any idea how pathetic and foolish that sounds? Right up there with "man will never fly" and "everything that can be invented has been invented." There are 9 man-made objects on their way out of the solar system right now. One reached interstellar space over 5 years ago. Is it that hard for you to imagine "escape from our planetary system" is possible? How about in a hundred years or a hundred thousand years?

Yes, I agree I have always maintained that we humans are capable of achieving of practically anything once determination sets in. I am confident that we will overcome obstacles and colonize a couple of planets in our SS and from there beyond the SS.The only thing I see that would stop us would be a global WWIII but fortunately recent events are encouraging showing that we are capable of avoiding that too.
Mark Thomas
4.8 / 5 (4) Jun 06, 2018
Merrit, it is not hard to imagine that someday soon we could build robots sophisticated enough to act as parents. Then we could send the humans as frozen eggs and sperm or frozen embryos. Maybe we could even send the humans as digitally stored code corresponding to DNA sequences that could be used to form actual DNA in cells after an extremely long journey. The robots could also help build shelters and terraform these strange, new worlds. Once humans have spread to colonies in nearby star systems the need for warp drive or the equivalent will be readily apparent.

I don't particularly favor this approach, but as a thought experiment it suggests that interstellar colonization by human beings is scientifically possible even without FTL.
howhot3
3 / 5 (2) Jun 07, 2018
Professional fear monger here. Boo. Run in terror flakey right wing stooges and climate change deniers.

Having said that, here is my dark view on what will happen to mankind (not some alien world) with our current climate situation. All 4 scenarios will happen based on the region you live. They all result in a very bad place. We are past the 400ppm CO2 concentrations already and easily heading to 800ppm by 2050 and 1500ppm by 2100. Green house gases will capture heat exponentially. Somewhere after 2050 you will see all the scenarios; wars over water, food, and stagnation of trade as societies crumble in excessive heat waves, Massive migrations towards to polar regions will cause massive hostilities and clashes as migrants try to escape the pestilence of of persistent heat, drought, and barren land. Whole cities will be abandoned due to lack of functioning AC.

But I suspect it could be worst with the weapons of war we posses. Nope, no way do we survive.
eachus
5 / 5 (2) Jun 07, 2018
I don't particularly favor this approach, but as a thought experiment it suggests that interstellar colonization by human beings is scientifically possible even without FTL.


Isacc Arthur Has a very nice set of videos about space travel and colonization. https://www.youtu...g/videos What you conclude from it is that if interstellar travel is very difficult, we will end up building some form of Dyson Sphere around the sun. Once the population is in the high quadrillions, interstellar travel of any of various forms will be pretty cheap.

However, I think that FTL is possible and will be developed. But I suspect that going faster than a few times the speed of light may be impossible for engineering reasons.

There is another option. If O'Neill cylinders are a common part of the Dyson swarm, one, or a group of them could pull up stakes and move to a new system. No need for a long time away from home, you would bring home with you.
eachus
3 / 5 (2) Jun 07, 2018
But I suspect it could be worst with the weapons of war we posses. Nope, no way do we survive.


First, the only way the human race survives is if we use this current window of opportunity to put up one or more space elevators, and become an interplanetary civilization.

I don't want to fear monger, but I am not worried at all about rising global temperatures. The historical record is clear, temperatures increase gradually, then a VEI 6 or higher volcano occurs--or rarely, an asteroid. Read about what happened when Mt Tambora (VEI 7) blew its top just over 200 years ago. The next year was called either "The year without a summer," or "Eighteen hundred and froze to death." Estimates of global temperature change were about 2 degrees C or 4 degrees F. Doesn't matter, there are potential VEI 8 sites out there--including Yellowstone--that would be ten times as severe.

Putting all our eggs in this one basket is crazy, independent of which disaster we fear most.
Mimath224
not rated yet Jun 07, 2018
I think we have separate natural disasters and from anthropogenic disasters. The natural ones could strike at any time and depending on how widespread we may/may not survive. For example, Asteroid Bennu has, apparently 1/2600 chance of colliding with Earth somewhere around the year 2135. Maybe then we will have the means to do something about it and maybe we won't so it's all a bit 'iffy'. What WOULD be certain is that if Bennu does arrive on our doorstep so to speak, no one is going to be able to deny it. Climate Change is an on going natural process but does the present Global Warming have an anthropogenic cause? The world seems divided. And then there are countries that really don't care one way or the other. I know, I live in such a country and none of the Major countries or the EU has been able to persuade them otherwise. Are there many countries like this? I hope there are not, for if so then we humans are in for a struggle...assuming an anthropogenic cause, of course.
ThereIsNoDarkMatter
1 / 5 (1) Jun 10, 2018
Unavoidably causing their self-destruction in a suicidal frenzy of greed and hate.

quite an emotional remark for a rational science discussion.
ThereIsNoDarkMatter
1 / 5 (1) Jun 10, 2018
humans make too much poop... we invent sewers. humans heat up environment... then we will make giant air conditioners using space mirrors or spray light reflecting aerosols in the high atmosphere.

imagine if we were asked to poop less when the first cities appeared, rofl!

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